The poem's title tells readers that it takes place in Harlem, a historically Black neighborhood of New York City, and that it's about a dancer. The poem's first line then dives right into the action, creating the impression of a scene that has been going on for some time.
The "dancer" of the title is apparently an exotic one, given the references to her lack of clothing and the raucous atmosphere around her. The mention of rowdy young people laughing and clapping suggests that this is all happening in a nightclub, while the mention of "young prostitutes" highlights the seediness of this club (remember that this poem was written around the 1920s, when social mores were even stricter than they are nowadays).
Already, though, the poem suggests that not all is as it appears to be. The fact that these "prostitutes" are "young," for example, suggests their innocence. The fact that the other audience members are "youths" does the same, perhaps implying that young people are forced to grow up quickly in Harlem.
The sounds of the poem evoke its lively atmosphere. The first line's meter, for instance, is not the typical iambic pentameter of an English sonnet (five iambs, or da-DUMs, in a row)—at least, not exactly. The first two feet are indeed iambs, but then the stressed and unstressed syllables get jumbled around a bit:
Applaud- | ing youths | laughed with | young prost- | itutes
This jumpy metrical variation emphasizes the rowdiness of the audience members, but it's not just meter that helps the first line create such a powerful atmosphere:
Consonance on the /l/ sound links the audience's applause and laughter, magnifying their sounds and making them seem perhaps more sinister than friendly.
- The words "youths" and "young" are connected by alliteration on the /y/ sound, while assonance connects "youths" and "prostitutes."
- The similar sounds of "youths" and "young prostitutes" also link these two groups of people together conceptually—a connection that's important because, as will soon be clear, both the dancer and the speaker feel detached from this crowd.
Also note how the poem opens by focusing on the audience, rather than the dancer herself. And when the dancer enters the poem in line 2, the audience focuses solely on the dancer's alluring physical body—her outward appearance, which is both "perfect" and "half-clothed." This time, the line follows iambic pentameter much more closely, with some extra stressed beats simply drawing attention to the dancer's body. The line is also divided exactly in the middle by the comma after "perfect," which creates a caesura:
And watched her perfect, || half-clothed body sway;
These structural aspects of the line reflect the dancer's body: the way it is "half-clothed" (the line is divided into neat halves) and its swaying (the iambs "sway" between unstressed and stressed syllables, and the evenly divided line itself seems to sway):
While the dancer's body may, in fact, be both very beautiful and "half-clothed," it's notable that the poetic techniques of the line emphasize the way the dancer is seen by the audience rather than the way she sees herself. By enacting the audience's image of the dancer as a "perfect, half-clothed body," the line emphasizes the way the audience is objectifying the dancer—and, implicitly, begins to offer a critique of that objectification.